Low noise wrist strength training ball

ABSTRACT

A low noise wrist strength training ball includes a case, a sleeve ring, a rotary body and a magnetic element. The sleeve ring is slidably disposed inside the case and is adapted for sliding relative to the case. The rotary body includes two protruding shafts opposite to each other. The two protruding shafts are pivotally connected to the sleeve ring and are adapted for rotating relative to the sleeve ring. The magnetic element is disposed in the sleeve ring and corresponds to one of the two protruding shafts. The magnetic element is adapted for magnetically attracting the one of the protruding shafts to press against the sleeve ring.

CROSS-REFERENCE TO RELATED APPLICATIONS

This non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s). 101223608 filed in Taiwan, R.O.C. on Dec. 5, 2012, the entire contents of which are hereby incorporated by reference.

BACKGROUND

1. Technical Field

The disclosure relates to a wrist strength training ball, and more particularly to a low noise wrist strength training ball.

2. Related Art

A wrist strength training ball that applies gyroscopic principles and mechanical means can be used to make the wrist strength training ball rotate. Users can hold the wrist strength training ball in the palm of their hand and rotate the wrist strength training ball. A large rotating force is produced by the effects of centrifugal force and inertia force. Therefore, the hand and shoulder muscles can be trained by the rotating force.

Conventional wrist strength training balls require a starting device to provide the wrist strength training balls with an initial kinetic energy making it easier for the users to start the wrist strength training ball. The starting device is, for example, a pull cord, a rack or an electrical device. However, regardless of which one of the pull cord, rack or electrical device is used to start the wrist strength training ball, the pull cord, the rack or the electrical device are all starting devices independently disposed outside of the wrist strength training ball. The users will not be able to operate the wrist strength training balls when the starting devices are lost. Therefore, some manufacturers install the starting device (e.g. elastic mechanism) inside the wrist strength training ball for the convenience of users to use the wrist strength training ball. Nevertheless, the changes on the structure and disposition of the wrist strength training ball will cause the wrist strength training ball to produce unexpected noise during operation. The users may give up on muscle training because of the unexpected noise. As a result, it will be less desirable for the users to purchase the wrist strength training ball.

SUMMARY

An embodiment of the disclosure provides a low noise wrist strength training ball comprising a case, a sleeve ring, a rotary body and a magnetic element. The sleeve ring is slidably disposed inside the case and adapted for sliding relative to the case. The rotary body comprises two protruding shafts opposite to each other. The two protruding shafts are pivotally connected to the sleeve ring and are adapted for rotating relative to the sleeve ring. The magnetic element is disposed in the sleeve ring and is corresponding to one of the two protruding shafts. The magnetic element is adapted for magnetically attracting the one of the protruding shafts to press against the sleeve ring.

Another embodiment of the disclosure provides a low noise wrist strength training ball comprising a case, a sleeve ring, a rotary body and a shock damping component. The sleeve ring is slidably disposed inside the case and sliding relative to the case. The rotary body comprises two protruding shafts opposite to each other. The two protruding shafts are pivotally connected to the sleeve ring and are adapted for rotating relative to the sleeve ring. The shock damping component is disposed on the sleeve ring and corresponds to one of the two protruding shafts. The shock damping component is pressed against the one of the protruding shafts.

Yet another embodiment of the disclosure provides a low noise wrist strength training ball comprising a case, a sleeve ring, and a rotary body. The case comprises a first case portion, a second case portion, a first concave portion and a second concave portion. The first concave portion and the second concave portion are disposed on the circumference of the first case portion and the circumference of the second case portion, respectively. The second case portion is installed on the first case portion for forming an accommodating space together. The first concave portion and the second concave portion form an annular groove together. The annular groove has a contact surface. Each of the first concave portion and the second concave portion has an inner surface and an outer surface opposite to each other. The contact surface is connected to the inner surfaces. The sleeve ring is slidably disposed inside the annular groove and is adapted for sliding relative to the case. The rotary body comprises two protruding shafts opposite to each other. The two protruding shafts are pivotally connected to the sleeve ring and are adapted for rotating relative to the sleeve ring. The two protruding shafts are respectively attached on the contact surface. Ends of the two protruding shafts are disposed between the inner surfaces and the outer surfaces respectively.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure will become more fully understood from the detailed description given herein below for illustration only, thus does not limit the disclosure, wherein:

FIG. 1 is a perspective view of a low noise wrist strength training ball with an opened first case portion according to a first embodiment of the disclosure;

FIG. 2 is an exploded perspective view of FIG. 1;

FIG. 3 is a sectional view of the first case portion in FIG. 1 installed in a second case portion;

FIG. 4 is a partial enlarged sectional view of FIG. 3;

FIG. 5 is a sectional view of the low noise wrist strength training ball according to a second embodiment of the disclosure; and

FIG. 6 is a partial enlarged sectional view of FIG. 5.

DETAILED DESCRIPTION

In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. It will be apparent, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are schematically shown in order to simplify the drawing.

Please refer to FIGS. 1 and 2 together. FIG. 1 is a perspective view of a low noise wrist strength training ball with an opened first case portion according to a first embodiment of the disclosure and FIG. 2 is an exploded perspective view of FIG. 1.

As shown in FIGS. 1 and 2, a low noise wrist strength training ball 10 in this embodiment comprises a case 100, a sleeve ring 200, a rotary body 300 and a magnetic element 400. The sleeve ring 200 is slidably disposed inside the case 100 and is adapted for sliding relative to the case 100. The rotary body 300 comprises two protruding shafts 310 that are disposed oppositely to each other. The two protruding shafts 310 are pivotally connected to the sleeve ring 200 and are adapted for rotating relative to the sleeve ring 200. The magnetic element 400 is a magnet. The magnetic element 400 is disposed in the sleeve ring 200 and corresponds to one of the two protruding shafts 310. The protruding shaft 310 is adapted for being magnetically attracted by the magnetic element 400 to press against the sleeve ring 200. Thereby, noise produced by the low noise wrist strength training ball 10 during usage can be reduced or eliminated.

Please refer to FIGS. 3 and 4. FIG. 3 is a sectional view of a first case portion installed in a second case portion in FIG. 1 and FIG. 4 is a partial enlarged sectional view of FIG. 3. Typically, the case 100 comprises a first case portion 110 and a second case portion 120. A first concave portion 111 and a second concave portion 121 are disposed on the circumference of the first case portion 110 and the circumference of the second case portion 120, respectively. The second case portion 120 is installed in the first case portion 110 to form an accommodating space 130 together. The first concave portion 111 and the second concave portion 121 are disposed in an annular groove 140. In other words, the annular groove 140 is disposed on an inner wall surface of the case 100 forming the accommodating space 130.

As shown in FIG. 4, in this embodiment and some other embodiments, the annular groove 140 has two contact surfaces 141 opposite to each other. The two contact surfaces 141 are disposed on the first case portion 110 and the second case portion 120, respectively. The first concave portion 111 has an inner surface 112 and an outer surface 113 relatively close to or farther away from the rotary body 300. The contact surface 141 of the first case portion 110 is connected to the inner surface 112. The second concave portion 121 has an inner surface 122 and an outer surface 123 relatively close to or further away from the rotary body 300. The contact surface 141 of the second case portion 120 is connected to the inner surface 122.

In this embodiment, the rotary body 300 becomes inclined when it rotates. In other words, when the rotary body 300 rotates, an end of one of the two protruding shafts 310 is in point-to-point contact with the contact surface 141, of the first case portion 110, when it is pressed against the contact surface 141 of the first case portion 110. Similarly, an end of the other protruding shaft 310 is in point-to-point contact with the contact surface 141 of the second case portion 120 when it is pressed against the contact surface 141 of the second case portion 120. As a result, the two contact surfaces 141 may be worn out easily, which affects the rotation of the rotary body 300. Therefore, in order to reduce the wear between the protruding shafts 310 and contact surfaces 141, the contact surfaces 141 of this embodiment are also inclined. The degree of inclination of the contact surfaces 141 is roughly equal to that of the rotary body 300 during rotation. Furthermore, the ends of the two protruding shafts 310 are suspended between the inner surfaces 112 and 122 as well as the outer surfaces 113 and 123, respectively, to cause the contact surfaces 141 and the protruding shafts 310 to be parallel to each other, and to cause the surfaces of the middle sections of the two protruding shafts 310 to be attached to the contact surfaces 141 in order to increase the contact areas between the two protruding shafts 310 and the contact surfaces 141. Therefore, the damages of the annular groove 140 caused by the protruding shafts 310 during the rotation of the rotary body 300 can be reduced, and the life span of the low noise wrist strength training ball 10 can be prolonged. However, the technical characteristics of the first case portion 110 and the second case portion 120 respectively, comprising the first concave portion 111 and the second concave portion 121, should not be limited to being disposed in the low noise wrist strength training ball 10 with the magnetic element 400. In other embodiments, the first concave portion 111 and the second concave portion 121 are also be disposed in wrist strength training balls without the magnetic element 400.

Additionally, the surfaces of the two protruding shafts 310 contacting with the contact surfaces 141 can make the connection between the protruding shafts 310 and the case 100 to be steadier, and the noise produced by the low noise wrist strength training ball 10 during usage can be reduced or eliminated.

As shown in FIG. 2, the sleeve ring 200 is disposed in the annular groove 140 in order so the sleeve ring 200 can slide relative to the case 100. The sleeve ring 200 comprises two pivotal portions 210 opposite to each other. Each of the pivotal portions 210 has a through hole 211, and the two through holes 211 have the same axis. One of the two pivotal portions 210 has an accommodating groove 212.

As shown in FIGS. 2 and 3, the rotary body 300 is disposed inside the accommodating space 130, and the annular groove 140 surrounds the rotary body 300. The two protruding shafts 310 penetrate through the two through holes 211, respectively and press against the annular groove 140 such that the rotary body 300 is adapted for driving the sleeve ring 200 to rotate and slide relative to the case 100. Furthermore, the rotary body 300 has a hollow groove 320, and one of the two protruding shafts 310 is disposed inside the hollow groove 320. The sleeve ring 200 is made of plastic, and therefore the sleeve ring 200 is slightly elastic and can absorb shock.

In this embodiment and some other embodiments, the low noise wrist strength training ball 10 further comprises an elastic device 500. A side of the elastic device 500 is fixed inside the hollow groove 320 of the rotary body 300, and another side of the elastic device 500 is fixed on an inner circumference of the sleeve ring 200 facing the hollow groove 320. The above-mentioned accommodating groove 212 is disposed in the pivotal portion 210 which is assembled with the elastic device 500.

The magnetic element 400 is disposed in the accommodating groove 212. The magnetic element 400 is adapted for magnetically attracting the one of the protruding shafts 310 close to the elastic device 500 to press against an inner wall surface of the one of the through holes 211 close to the elastic device 500. Therefore, the shock of the protruding shaft 310 can be suppressed by the pivotal portion 210, and an intensity of the noise produced by the low noise wrist strength training ball 10 during usage can be reduced as well. The principles of shock damping and noise reduction will be described together hereinafter.

The following takes the magnetic element 400 as a magnet to describe the principles of shock damping and noise reduction of the low noise wrist strength training ball 10. Please refer to FIG. 3, the reasons why the low noise wrist strength training ball 10 in this embodiment produces noise easily is described first. Because the low noise wrist strength training ball 10 in this embodiment comprises the elastic device 500, the hollow groove 320 has to be formed in the rotary body 300 such that the elastic device 500 has the space to be disposed in the hollow groove 320. However, because of the disposition of the hollow groove 320, a supporting strength of the protruding shaft 320 of the rotary body 300, disposed in the hollow groove 320, becomes weaker and the low noise wrist strength training ball 10 will produce shock easily during usage. More specifically, because it is not possible to design a reinforced structure for the protruding shaft 310 that is disposed in the hollow groove 320, a suspension length D1 of the protruding shaft 310, disposed in the hollow groove 320, is far longer than a suspension length D2 of the other protruding shaft 310. Therefore, the protruding shaft 310, disposed in the hollow groove 320, will produce shock more easily when it rotates relative to the annular groove 140. Furthermore, because the hollow groove 320 has the effects similar to a resonating chamber, the noise produced by the sway and the shock of the protruding shaft 310, disposed in the hollow groove 320, will be magnified. As a result, the users will be affected easily and the users will give up on their muscle training.

Because the magnetic element 400 of this embodiment is disposed inside the accommodating groove 212 of the pivotal portion 210 close to the hollow groove 320; when the protruding shaft 310, disposed in the hollow groove 320, starts to sway or shock, the magnetic element 400 will magnetically attract the protruding shaft 310 to press against the inner wall surface of the corresponding through hole 211 on the sleeve ring 200. Therefore, the shock of the protruding shaft 310 can be suppressed by the shock damping capability of the sleeve ring 200, and an intensity of the noise produced by the low noise wrist strength training ball 10 during usage can be reduced. In practical tests, a noise level of the operating low noise wrist strength training ball 10 of this embodiment is 61 decibels, which is a level humans feel comfortable with.

Please refer to FIGS. 5 and 6. FIG. 5 is a sectional view of the low noise wrist strength training ball according to a second embodiment of the disclosure. FIG. 6 is a partial enlarged sectional view of FIG. 5.

The low noise wrist strength training ball 10 of this embodiment comprises the case 100, the sleeve ring 200, the rotary body 300 and a shock damping component 600. The sleeve ring 200 is slidably disposed inside the case 100 and is adapted for sliding relative to the case 100. The rotary body 300 comprises the two protruding shafts 310 disposed oppositely to each other. The two protruding shafts 310 are pivotally connected to the sleeve ring 200 and are adapted for rotating relative to the sleeve ring 200. The shock damping component 600 is disposed in the sleeve ring 200 and corresponds to one of the two protruding shafts 310. The shock damping component 600 is pressed against the protruding shaft 310 for suppressing the shock of the protruding shaft 310. Therefore, the noise produced by the low noise wrist strength training ball 10 during usage can be reduced or eliminated.

Typically, the sleeve ring 200 comprises the two pivotal portions 210 opposite to each other. The two protruding shafts 310 are pivotally connected to the two pivotal portions 210 respectively such that the rotary body 300 is adapted for rotating relative to the sleeve ring 200.

In this embodiment and some other embodiments, the low noise wrist strength training ball 10 further comprises the elastic device 500. The rotary body 300 has the hollow groove 320. One end of the elastic device 500 is fixed inside the hollow groove 320, and the other end of the elastic device 500 is fixed on one of the two pivotal portions 210 of the sleeve ring 200.

The pivotal portion 210, assembled with the elastic device 500, has the accommodating groove 212. The accommodating groove 212 is close to the pivotal portion 210 which is assembled with the elastic device 500. The shock damping component 600 is disposed in the accommodating groove 212 such that the shock damping component 600 is adapted for being pressed against the protruding shaft 310 which is close to the elastic device 500.

The shock damping component 600 comprises an elastic element 610 and a shock absorbing body 620. The elastic element 610 and the shock absorbing body 620 are disposed in the accommodating groove 212. The shock absorbing body 620 is closer to the protruding shaft 310 than the elastic element 610. The shock absorbing body 620 is, for example, made of materials such as rubber or plastic with certain elasticity. Normally, the elastic element 610 causes the shock absorbing body 620 to move toward the protruding shaft 310 for pressing against the protruding shaft 310 close to the elastic device 500 such that the shock absorbing body 620 may suppress the shock of the protruding shaft 310.

According to the low noise wrist strength training ball in the disclosure, because the magnetic element is disposed in the pivotal portion close to the elastic device, and the protruding shaft is magnetically attracted by the magnetic element to press against the sleeve ring, the shock produced by the operation of the protruding shaft can be suppressed by the shock absorbing capability of the sleeve ring. Therefore, unexpected noise is prevented from being produced by the low noise wrist strength training ball.

Furthermore, the extending directions of the contact surfaces and the two protruding shafts are parallel to each other, and the ends of the two protruding shafts are disposed between the inner surfaces and the outer surfaces respectively. Therefore, because the ends of the two protruding shafts are suspended between the inner surfaces and the outer surfaces without contacting with the contact surfaces, the surfaces of the two protruding shafts can be in contact with the contact surfaces, instead of in a point-to-point contact, so as to increase the contact areas between the two protruding shafts and the contact surfaces. Therefore, the damages of the annular groove caused by the protruding shafts during the rotation of the rotary body can be reduced, and the life span of the low noise wrist strength training ball can be prolonged. Additionally, the surface contact between the two protruding shafts and the contact surfaces can make the connection between the protruding shafts and the case to be steadier, and the noise produced by the low noise wrist strength training ball during usage can be reduced or eliminated.

Furthermore, because the pivotal portion of the elastic device is disposed with the shock damping component, the shock absorbing body of the shock damping component can be pressed against the protruding shaft so as to suppress the shock produced by the rotation of the protruding shaft and to prevent unexpected noise from being produced by the low noise wrist strength training ball. 

What is claimed is:
 1. A low noise wrist strength training ball, comprising: a case; a sleeve ring slidably disposed inside the case and adapted for sliding relative to the case; a rotary body comprising two protruding shafts opposite to each other, the two protruding shafts being pivotally connected to the sleeve ring and adapted for rotating relative to the sleeve ring; and a magnetic element disposed in the sleeve ring and being corresponding to one of the two protruding shafts, and wherein the magnetic element is adapted for magnetically attracting the one of the protruding shafts to press against the sleeve ring.
 2. The low noise wrist strength training ball according to claim 1, wherein the case has an accommodating space and an annular groove, the annular groove is disposed on an inner wall surface of the case forming the accommodating space therein, the rotary body is disposed in the accommodating space, the annular groove surrounds the rotary body, the two protruding shafts are pressed against the annular groove, respectively.
 3. The low noise wrist strength training ball according to claim 2, wherein the case comprises a first case portion and a second case portion, the second case portion is installed on the first case portion to form the accommodating space together.
 4. The low noise wrist strength training ball according to claim 1, wherein the sleeve ring comprises two pivotal portions opposite to each other, the two protruding shafts are pivotally connected to the two pivotal portions, respectively, for causing the rotary body to rotate relative to the sleeve ring.
 5. The low noise wrist strength training ball according to claim 4, further comprising an elastic device, the rotary body having a hollow groove, one side of the elastic device being fixed inside the hollow groove, and the other side of the elastic device being fixed on one of the two pivotal portions of the sleeve ring.
 6. The low noise wrist strength training ball according to claim 5, wherein the magnetic element is disposed in the one of the pivotal portions assembled with the elastic device, and the magnetic element is adapted for magnetically attracting the protruding shaft close to the elastic device to press against the one of the pivotal portions close to the elastic device.
 7. The low noise wrist strength training ball according to claim 6, wherein each of the two pivotal portions has a through hole, the two protruding shafts penetrate through the two through holes, respectively, the one of the pivotal portions assembled with the elastic device has an accommodating groove, the accommodating groove is close to the through hole of the one of the pivotal portions assembled with the elastic device, the magnetic element is installed in the accommodating groove for magnetically attracting the one of the protruding shafts close to the elastic device to press against an inner wall surface of the corresponding through hole.
 8. A low noise wrist strength training ball, comprising: a case; a sleeve ring slidably disposed inside the case and sliding relative to the case; a rotary body comprising two protruding shafts opposite to each other, the two protruding shafts being pivotally connected to the sleeve ring and adapted for rotating relative to the sleeve ring; and a shock damping component disposed on the sleeve ring and being corresponding to one of the two protruding shafts, and the shock damping component being pressed against the one of the protruding shafts.
 9. The low noise wrist strength training ball according to claim 8, wherein the sleeve ring comprises two pivotal portions opposite to each other, the two protruding shafts are pivotally connected to the two pivotal portions, respectively, for causing the rotary body to rotate relative to the sleeve ring.
 10. The low noise wrist strength training ball according to claim 9, further comprising an elastic device, the rotary body having a hollow groove, one side of the elastic device being fixed inside the hollow groove, and the other side of the elastic device being fixed on one of the two pivotal portions of the sleeve ring.
 11. The low noise wrist strength training ball according to claim 10, wherein the one of the pivotal portions assembled with the elastic device has an accommodating groove, the accommodating groove is close to the one of the pivotal portion assembled with the elastic device, the shock damping component is installed in the accommodating groove for the shock damping component to press against the one of the protruding shafts close to the elastic device.
 12. The low noise wrist strength training ball according to claim 11, wherein the shock damping component comprises an elastic element and a shock absorbing body, the elastic element and the shock absorbing body are disposed in the accommodating groove, and the shock absorbing body is closer to the protruding shaft than the elastic element normally, and the elastic element causes the shock absorbing body to move toward the one of the protruding shafts for pressing against the one of the protruding shafts close to the elastic device.
 13. A low noise wrist strength training ball, comprising: a case comprising a first case portion, a second case portion, a first concave portion and a second concave portion, the first concave portion and the second concave portion being disposed on the circumference of the first case portion and the circumference of the second case portion, respectively, the second case portion being installed on the first case portion for forming an accommodating space together, the first concave portion and the second concave portion forming an annular groove together, the annular groove having a contact surface, each of the first concave portion and the second concave portion having an inner surface and an outer surface opposite to each other, and the contact surface being connected to the inner surfaces; a sleeve ring slidably disposed inside the annular groove and adapted for sliding relative to the case; and a rotary body comprising two protruding shafts opposite to each other, the two protruding shafts being pivotally connected to the sleeve ring and adapted for rotating relative to the sleeve ring, the two protruding shafts being respectively attached on the contact surface, and ends of the two protruding shafts being disposed between the inner surfaces and the outer surfaces respectively. 